PECARN head injury rule (≥ 2 years)
Need for CT after minor head trauma in children aged 2–17 (GCS 14–15)
Sources last checked: 2026-10-13
PECARN head injury rule (≥ 2 years)
Need for CT after minor head trauma in children aged 2–17 (GCS 14–15)
Risk of clinically important TBI < 0.05 % in the derivation cohort.
Only for children aged 2–17 years presenting within 24 h of blunt head trauma with GCS 14–15. Not for penetrating trauma, known brain tumour, bleeding disorders, ventricular shunts, or suspected non-accidental injury.
Interpretation
| No predictor — PECARN: CT not recommended | Risk of clinically important TBI < 0.05 % in the derivation cohort. |
|---|---|
| Intermediate — observation versus CT | Risk ≈ 0.9 %. PECARN leaves the choice between observation and CT to clinical factors: multiple versus isolated findings, worsening symptoms, physician experience, parental preference. |
| High risk — PECARN: CT recommended | Risk of clinically important TBI ≈ 4.3 %. |
What is the PECARN head injury rule (≥ 2 years)?
This is the PECARN rule for children aged 2–17 years, derived and validated by Kuppermann and colleagues in 2009 in more than 31,000 children with minor blunt head trauma (GCS 14–15). Children with none of the six predictors had a negative predictive value of 99.95 % for clinically important traumatic brain injury.
When to use it
- Children 2–17 years within 24 h of blunt head trauma with GCS 14–15
- Deciding between CT, observation and discharge
- Structured shared decision-making with families
When not to use it
- Penetrating trauma, known brain tumour, pre-existing neurological disorder, bleeding disorder or ventricular shunt
- Suspected non-accidental injury
- GCS ≤ 13
How it is calculated
High risk (PECARN: CT recommended): GCS 14 or other altered mental status, OR signs of basilar skull fracture. Intermediate (observation vs CT): history of LOC, OR vomiting, OR severe mechanism, OR severe headache. Severe mechanism: motor-vehicle crash with ejection, rollover or death of another passenger; pedestrian or unhelmeted cyclist struck by a motorised vehicle; fall > 1.5 m (5 ft); head struck by a high-impact object. No predictor: PECARN does not recommend CT.
Clinical pearls and limitations
- Only for children aged 2–17 years presenting within 24 h of blunt head trauma with GCS 14–15. Not for penetrating trauma, known brain tumour, bleeding disorders, ventricular shunts, or suspected non-accidental injury.
- Isolated vomiting, isolated headache or isolated LOC carry a low risk of clinically important TBI.
- PECARN lists worsening symptoms during observation among the factors favouring CT.
- Severe mechanism includes falls from more than 1.5 m in this age group.
Frequently asked questions
What are the PECARN criteria for children over 2?
High risk: GCS 14, other altered mental status or signs of basilar skull fracture. Intermediate: loss of consciousness, vomiting, severe mechanism or severe headache.
Does vomiting after head injury always need a CT?
No. Under PECARN, vomiting alone places a child in the intermediate group, where observation versus CT is decided on clinical factors.
How accurate is the PECARN rule?
In validation, sensitivity was 96.8 % and negative predictive value 99.95 % for clinically important brain injury in children aged 2 and over.
Evidence and guidelines
- Primary source: Kuppermann N et al. Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet 2009;374(9696):1160-1170.
- Babl FE et al. Accuracy of PECARN, CATCH, and CHALICE head injury decision rules in children: a prospective cohort study. Lancet 2017;389(10087):2393-2402.
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